Although the molecular events leading to the development of an ovarian epithelial carcinoma remain obscure, epidemiologic studies have identified family history as an important factor in determining an individuals risk for developing ovarian epithelial cancer. Compared with a lifetime risk of 1.6% (1 in 70 persons) in the general population, a woman with a single first-
degree relative with ovarian carcinoma has an approximate 5% risk of developing the disease. Another risk factor for developing ovarian epithelial cancer is nulliparity. Conversely, the use of oral contraceptives reduces the risk of ovarian epithelial cancers. Use of the oral contraceptive for 5 years reduced the risk of ovarian epithelial cancers by about 50%.4 Although the majority of ovarian epithelial cancers occur sporadically, approximately 10% occur as a result of a hereditary predisposition, such as a germline mutation in the BRCA1 or BRCA2 genes or from the hereditary nonpolyposis colorectal (Lynch II) syndrome.